The aim of the proposed project is to conduct an analysis of data which have been gathered through a combination of questionnaire and clinical interview procedure with approximately 100 Vietnam combat veterans for whom a definitive diagnosis of post-traumatic stress disorder (PTSD) has been made. The analysis of this existing data base is seen as a timely and cost-effective means of obtaining information concerning the relationship of veterans' precombat, combat, and postcombat exeriences to the development of differing manifestations of PTSD, which will heighten understanding of the etiology and dynamics of the disorder and will contribute to the treatment of PTSD and related difficulties.